Integrated steel mills and the like typically have coke ovens and/or oxygen steelmaking furnaces and use excess associated gases for heating and power generation. In many applications, it would be desirable to use the associated coke oven gas (COG) and/or the associated basic oxygen furnace gas (BOFG) to reduce iron oxide to metallic iron, in the form of direct reduced iron (DRI), hot direct reduced iron (HDRI), or hot briquetted iron (HBI). Both COG and BOFG contain significant percentages of carbon monoxide (CO) and hydrogen (H2), which are the primary reductants for reducing iron oxide to metallic iron. The COG also contains 20+% methane (CH4), which, under the proper conditions, may be reformed with carbon dioxide (CO2) and water (H2O) to form CO and H2. BOFG may contain up to 20% nitrogen (N2), which may build up to very high levels in a recirculating system, for example.